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Hugh Pickens DOT Com writes "Elizabeth Barber reports in the Christian Science Monitor that when a CH-46E Sea Knight helicopter plummeted into the ground at more than 30 miles per hour, there was jubilation from the scientists on the ground at the culmination of some two years of preparation to test a helicopter's crashworthiness. 'We designed this test to simulate a severe but survivable crash under both civilian and military requirements,' says NASA lead test engineer Martin Annett. 'It was amazingly complicated with all the planning, dummies, cameras, instrumentation and collaborators, but it went off without any major hitches.' During the crash, high-speed cameras filming at 500 images per second tracked the black dots painted on the helicopter, allowing scientists to assess the exact deformation of each part of the craft, in a photographic technique called full field photogrammetry. Thirteen instrumented crash test dummies and two un-instrumented manikins stood, sat or reclined for a potentially rough ride. The goal of the drop was to test improved seat belts and seats, to collect crashworthiness data and to check out some new test methods but it was also to serve as a baseline for another scheduled test in 2014. 'It's extraordinarily useful information. I will use this information for the next 20 years,' says Lindley Bark, a crash safety engineer at Naval Air Systems Command on hand for the test. 'Even the passenger airplane seats in there were important to us because we fly large aircraft that have the same type of seating."'

Oh there must have been a huge breakthrough in airbag technology I never heard about...how do these new airbags restrain a person in their seat to stop them being flung out of the vehicle during a crash, like seatbelts are designed to do?

I cant see any mechanism for how this could possibly be possible with airbags.

"how do these new airbags restrain a person in their seat to stop them being flung out of the vehicle during a crash, like seatbelts are designed to do?"

Same way they have in the past - inflate over every opening and block you from going out. That is one of the few primary functions of wheel and dash airbags - to keep you from flying through the windshield. We have side curtain airbags that deploy and somewhat prevent you from flying out the side windows as well.

I was under the impression that using airbags without seatbelts would actually cause injuries, mainly due to passengers being bounced around uncontrollably. In a car crash, the head and neck are flung forward by the collision and then back by the airbag rebound, potentially causing whiplash injuries.

If you're wearing a seatbelt, however, it will keep your body stable while the airbag slows your head's travel forward.

Please, correct me if I'm wrong but the two seem to complement each other quite well.

> but hitting an airbag while bouncing around a cabin is still better than hitting something harder.

Are you certain about that? Yes the airbag is softer than most other parts of the interior, but if you're not slowed by a seatbelt then you will hit it while it's still in it's early inflation phase, and moving *very* much faster than anything else, up to 200mph. If you were traveling at 60mph and hit something immobile without seatbelts restraining you then that airbag will be a slap in the face by a pi

Dixit Wikipedia:"To provide crash protection for occupants not wearing seat belts, U.S. airbag designs trigger much more forcefully than airbags designed to the international ECE standards used in most other countries. "

When you are not wearing a seatbelt, the airbag will get there earlier to compensate. Maybe you were thinking about children, which represent more than half the airbag deaths.

That's only true in Europe where they are a true secondary restraint system unlike in the United States where although classified as a secondary restraint, the specifications ensure that current airbags are actually a primary restraint system.

Out of every accident I've been in where airbags deployed, the seatbelt did NOTHING to lock down and keep me in place.

How many crashes have you been in where airbags have deployed?

And how many crashes in total?

In my 20 years of driving... actually almost 25 years... I've had (1) drive-away-able (my inexperience, came into contact with the kerb, very hard, while still a learner) ; (2) drive-away-able (both stopped out of contact, but came together on the bounce in the springs) ; (3) walk-away, no airbag

"And exactly how many accidents have there been that involve a person going through the windshield or side window when wearing a seat belt, even without airbags? "

USA alone or worldwide? I can name several celebrities that have been in auto accidents where they got ejected while wearing a seatbelt. The drummer for Def Leppard, for example, had his arm torn off by the seatbelt as he got ejected.

Exact numbers can't be had as there's someone likely getting ejected from their car, while wearing a seatbelt, ever

I was under the impression that using airbags without seatbelts would actually cause injuries, mainly due to passengers being bounced around uncontrollably.

It's not so much that you bounce around uncontrollably; it's that with the airbag in front of your upper body, and nothing around your waist, all your forward momentum results in your sliding under the airbag into the floor space in front of your seat, where by "sliding" I mean "in a high-speed crash, being crumpled and crushed":-(

Do not confuse with "Whopperchild". Actually, "mannequin" IS a sexist word. It is the Dutch word "manneken" (= little man) as pronounced by the French. At that point in history, they did not use starving women to show clothes.

If you knew anything about helicopters you'd know that 30mph is VERY relevant. Depending on what you're flying, your load, and weather conditions, 30mph (just over 2600 feet per minute) is approximately the speed you'd hit the ground in an autorotation if you did not flare or try to lessen the rate with only collective (which would not be very effective at all). In some helicopters the vertical descent rate in an auto is much lower but 2600 is a good ballpark number.

If you knew anything about helicopters you'd know that 30mph is VERY relevant.

Indeed. In 1981, I was a young Marine grunt on an exercise in Camp Lejeune, North Carolina. We were riding CH-46s into an LZ and the bird right behind mine lost power and auto-gyrated into the ground. I reached the treeline, and turned just in time to see it hit the ground. The helicopter was badly damaged, and the Marines on board were shaken up, but no one was hurt.

Considering the accident rate for helicopters for the last couple years was 4-7 per 100,000 flying hours, while the fatal accident rate was 0.75-1.3 per 100,000, non-fatal accidents are a lot more common than fatal. A large portion of crashes involve take off and landing, or involve slow conditions when moving near the ground (e.g. lifting cargo). 30 mph is also about the speed of decent when in auto-rotation with no forward airspeed (although you could halve that at the minimum decent rate by moving forward). It seems like a 30 mph crash is pretty darn relevant to the real world. Or would you rather they test the effectiveness of seat belts in a crash they were 99% sure would be fatal regardless of seat belts?

The vast majority of helicopter crashes happen at 30 mph or less. Takeoff and landing accidents (from hover), loss of tailrotor effectiveness, settling with power, botched autorotations...these all tend to happen with the helicopter travelling at 30 mph or less.

Pity you don't seem to know jack shit about helicopters before unloading on a useful test.

In other news, NASA scientists announced confusion after attempting to crash a helicopter and failing despite repeated tries. The helicopter in question had, in various stages, had its stabilizers, fuel tank and even rotors removed. Despite all this, the helicopter remained aloft. "A failure," one scientist was quoted as saying. "We'll just have to shoot it down and try to crash one next next year after more planning." "A helicopter that cannot crash is a tremendous blow to science," another was heard arguing with another, "How are we supposed to obtain crash data with an infinitely levitating hunk of junk?"

Seems about time they start doing this... others have been doing similar activities with cars and planes. Helicopters have always seemed like a good idea to me, but generally are outside the financial reach of most of us (I've only been on one 20 minute sightseeing tour in Hawaii and it was $200 or $10/minute/passenger - there were 5 passengers). I wonder how much of my fare was to cover insurance premiums? Perhaps with more data for the actuaries to work with, the flight costs could drop to the point w

maybe there are some benefits as the reason of helicopters still existing today?

They can land places where other aircraft can't, and other VTOL (Vertical Take-Off and Landing ; the Harrier, essentially) systems are even less efficient.

The "tilt rotor" system ("Osprey"?) seemed for a time to be a potential competitor, but it seems as if the running costs are even higher than for helicopters, or the reliability is still too low. I don't know of any that are in commercial use - i.e. not military, rescue or ri

Given 5 passengers, I'll assume it to be a turbine helicopter. The absolute cheapest turbine (for operating costs) is about $600 per hour, or about $10 per minute. A mid-cost one will run you twice that, or more. So I'd say that half of the cost was aircraft maintenance. The pilot was likely nearly free. Many starting commercial pilots would pay to fly that trip. Insurance isn't that much, as flight-seeing trips are about as much in areas where insurance is essentially free.

The problem with flight actuaries is that there are so few crashes, and no easy way to differentiate between them. Almost all small craft crashes are pilot error, the most common being loading/power issues (just about all celebrities that went down were a pilot making an error to fly with an overloaded craft or into unacceptable weather.

Thanks for this explanation. So, I guess what you are saying is that to make things more economical, effort should be made into making the equipment less complicated and more rugged to reduce the maintenance aspects. I suppose this doesn't bode well for the personal jet packs we've all be promised for so many years!;-)

Simplicity doesn't help. Reliability helps more. Aircraft are expensive because they need such extensive maintenance. Engine rebuilds at very tight intervals, and very tightly controlled maintenance. Given issues with maintenance (just about all non-pilot errors are labeled maintenance), there are good reasons for it, but some basic changes in fundamentals around safety and costs may result in a similar. The engineering basics were designed around 100 year old engines. Most piston engines are carburet

NASA has been doing these tests for at least 35 years. The way they drop them hasn't changed much. Hell, even using the black dots isn't new for them. But all the media outlets carried this like it was something brand-new

Wel, it might have been quite new for the Christian Science Monitor.It's not likely helicopter crashes could be studied based on Bible [christianscience.com].

As I understand it, the short version of Christian Science is that God made everybody perfect, including their intelligence. We're supposed to be able to research, and learn, and improve our ability to use the resources we have. There is no forbidden knowledge, and no praise for ignorance. Most science is pretty universally accepted (and reported in the CSM).

Medicine is a somewhat different matter. Depending on the branch, all illness is either God's punishment or his plan, and that's the idea that leads th

I consider the CSM currently one of the most reliable and unbiased of US media sources out there.

For media news (social, political and the like), I can believe it.
Can you say the same for scientific type of news? (I'm indeed asking for opinion/references here, as opposed to raising the question to cast a doubt).

NASA has been doing these tests for at least 35 years. The way they drop them hasn't changed much. Hell, even using the black dots isn't new for them. But all the media outlets carried this like it was something brand-new

Wow! They probably remote flew a helicopter and then crashed it at a few miles per hour and it went up in a big ball of fire, but not before giving out some exciting new data taken by high-speed cameras placed....

*watches video*

It's a fuselage dropped from a crane not 30 feet from the ground. That was pretty anti-climatic...

The National Aeronautics and Space Administration (NASA) is the agency of the United States government that is responsible for the nation's civilian space program and for aeronautics and aerospace research.

Yup I mean you can absorb as much energy as you want with deformation and the like, but at the end of the day you are going from velocity v to velocity 0 in very little time indeed. So you can build safety devices all day long and that won't stop your heart from ripping itself off of your aorta, despite the fact you may have no external cuts and bruises...

That all depends on how little "very little time" is. Crashing at 30MPH [gsu.edu] is apparently survivable [wikipedia.org], but note that the forces involved are greatly diminished by having extra space (and therefore time) to decelerate. That comes from having a helicopter body that deforms properly, so it absorbs kinetic energy rather than transferring it into the occupants.

Ideally, in a vertical crash the humans end up sitting right on the ground, with the whole fuselage under them deformed at a rate that keeps the peak acceleration they experience in survivable levels. No, it certainly wouldn't be fun, but it could mean the difference between death and just having survivable internal damage... and if the rest of the helicopter's deformation has been engineered with as much care, there (also ideally) would be no hazard from debris, fire, or other environmental effects, so the victims are relatively safe just lying there waiting for rescue... Perhaps a crushed spine, but no disconnected vital organs.

Provided they wouldn't be likely to kill me before surgeons could fix things up, I think I'd rather go with a few disconnected vital organs. It's a lot harder to heal spinal cord/nerve damage enough to avoid at least part of the body being in serious pain long-term, and that kind of pain is a real bitch to get under control.

no hazard from debris, fire, or other environmental effects, so the victims are relatively safe just lying there waiting for rescue.

The main reason for helicopters existing (as opposed to being used by tourists for joy rides) is to get people and equipment to places that they can't get to otherwise. Since helicopters are expensive to operate, then it is almost always cheaper to build a road or use (multiple) all terrain vehicles. Except at sea.

A successful autorotation is a crash. Crash doesn't mean nose-down damage and casualties. It means unintended and less-than-properly-controlled landing. A hard landing in an airplane with no injuries and no damage is a "crash" so long as the forced involved made either likely. A successful autootation with no damage or injuries is also a crash. Though, many involved with such crashes will not treat them as such to keep records clean.

I gave the definition of an "aviation incident", which is often called a crash. Crash is not a technical term. "Aviation accident" is what you are stating "crash" is. There is no technical definition of "crash" defined by ICAO. So why are you so insistent the definition is "accident" and not "incident"?

Hell, by your reasoning I've crashed hundreds of times.

If every landing you perform is a hard landing, you may want to take up a new hobby.

"An aviation incident is defined as an occurrence, other than an accident, associated with the operation of an aircraft that affects or could affect the safety of operations."

Practicing an autorotation in a controlled situation isn't an incident, but having to use it (to prevent a crash) is. Many pilots (fixed wing, not helicopter) practice loss of power on every landing (at least while training), for when they'll need to do it for real. It's not as uncommon as people think. In smaller planes in the ri

Fuck crashing in a helo, the forces involved are rarely survivable for humans.

Bull.

Shit.

I know several people who've survived helicopter crashes. (I've come very close to being in one myself, but they managed to re-start the second engine before we hit the sea.)

From my observations of 25 years of North Sea helicopter crashes, about 3/4 of people survive. "Crash", of course, does cover a multitude of sins, from a controlled landing on the water (salt water ; the aircraft will be a total re-build, and may